Effect of N-substituents on protonation chemistry of trichlorophosphazenes

The protonation chemistry of trichlorophosphazene (R1NPCl3) with sulfonic acids (R2SO3H) was found to be affected by the N-substituents R1, yielding bis(sulfonyl)imides containing both R1 and R2, and mixed sulfonylphosphonyl imides containing either R1 or R2. In the formation of the latter a hitherto unobserved chemistry occurred. An intramolecular ‘imine SN2’ mechanism was proposed to rationalize the reactions observed.